218 THE URINE. 



The bases which are found in the urine in combination with hydro- 

 chloric acid, sulphuric acid, and phosphoric acid, are sodium, potas- 

 sium, calcium, magnesium, and ammonium. The latter, however, 

 occurs only in the urine of man and carnivorous animals. Calcium 

 and magnesium occur almost exclusively as phosphates, both of the 

 monacid and the diacid type. Traces, however, no doubt exist in 

 combination with hydrochloric acid and sulphuric acid as well, but 

 the greater portion of these two acids, as also of the phosphoric acid, 

 is found in the form of sodium and potassium salts. The ratio 

 between the two latter is usually placed at 3 : 5, in favor of sodium. 

 It is believed that the monacid phosphates of the alkaline earths, 

 and notably the calcium salts, are held in solution owing to the 

 presence of sodium chloride and the diacid phosphates of the alkalies, 

 to which the acidity of the urine is due. 



The alkaline phosphates normally exceed the earthy phosphates 

 by one-third, and it is to be noted that the latter are, in part at 

 least, also eliminated by the mucous membrane of the large intes- 

 tine. It consequently follows that estimation of the ratio between 

 the two forms of phosphates can only be of value when the amount 

 which is thus excreted is known. Practically, such a determination 

 is, however, impossible, as a variable amount of earthy phosphates 

 in fact, the greater portion of that which has been ingested is 

 directly eliminated through this channel. 



While the greater portion of the sulphuric acid which results from 

 the destruction of albumins within the tissues of the body is found 

 in the urine in combination with inorganic bases only, a variable 

 fraction also occurs united with certain aromatic substances which 

 are formed during intestinal putrefaction. The resulting bodies are 

 spoken of as conjugate or ethereal sulphates, and normally repre- 

 sent about one-tenth of the total amount of sulphuric acid that 

 appears in the urine. They comprise the alkaline salts of phenol, 

 indoxyl, and skatoxyl, and will be considered later. 



The mineral and conjugate sulphates together are spoken of as 

 the "acid" sulphur of the urine, in contradistinction to the so-called 

 neutral sulphur, which represents a variable fraction that escapes 

 oxidation in the body and finds its way into the urine as such. This 

 comprises such substances as thiosulphuric acid, tauro-carbaminic 

 acid, sulphocyanic acid, cystin, cystei'n, ethyl sulphide, etc. They 

 are described in detail at another place. 



In addition to the salts mentioned, a variable amount of carbo- 

 nates is found in every urine. In man and the carnivorous ani- 

 mals this is usually small ; but in the herbivorous animals large 

 quantities are normally found, and the alkaline reaction of such 

 urine is indeed largely referable to this source. The acid occurs in 

 combination with the alkalies and the alkaline earths, and owing to 

 the presence of the latter especially the urine of such animals is 

 normally turbid. 



